ISO 15500-14-2012 pdf free download

ISO 15500-14-2012 pdf free download.Road vehicles — Compressed natural gas (CNG) fuel system components — Part 14:Excess flow valve
Véhicules routiers — Corn posants des systèmes de combustible gaz nature! corn prime (GNC) — Partie 14: Valve de limitation de debit.
a) the manufacturer’s or agent’s name, trademark or symbol;
b) the model designation (part number);
c) the operating specifications (working pressure, temperature range, excess flow valve type. activation flow or M’. maximum flow when activated).
The following additional markings are recommended:
— the direction of flow (when necessary for correct installation);
— the type of fuel;
— electrical ratings (if applicable);
— the symbol of the certification agency;
— the type approval number;
— the serial number or data code;
— reference to this part of ISO 15500.
NOTE This Information can be provided by a suitable Identification code on at least one part of the component when
it consists of more than one part.
5 Construction and assembly
The excess flow valve shall comply with the applicable provisions of ISO 15500-1 and ISO 15500-2, and with
the tests specified in Clause 6 of this part of ISO 15500.
6 Tests
6.1 Applicability
There are many types of excess flow valves available. This part of ISO 15500 provides requirements for two different designs: internal and external excess flow valves. A valve of either design could be one of two different types: shut-off or flow-limiter. A shut-off valve should have a means of resetting after activation. As excess flow valve designs vary, so will the tests required.
The function of an excess flow valve can be achieved in other ways. For example, instead of using a mechanical device, an electronic system can be adopted to ensure the closing or limiting of the gas flow from the cylinder in an accident.
The tests required to be carried out are indicated in Table 1.
6.2 Hydrostatic strength
The purpose of the hydrostatic strength test is to establish the strength of the housing.
Test the excess flow valve according to the procedure for testing hydrostatic strength specified in Iso 15500-2.
For internal or external excess flow valves, the test pressure shall be 2,5 times the working pressure.
6.3 Leakage
The internal leakage test shall be conducted on shut-off type excess flow valves. Test the excess flow valve according to the procedure for leakage test as specified in ISO 15500-2 at the temperatures and pressures given in Table 2.ISO 15500-14-2012 pdf free download.